La Niña could be considered the climatological sibling of the slightly more famous El Niño. The two weather phenomena are often said to have great influence over the weather in Arizona.

Thing is, they don’t always deliver on that promise.

Remember the so-called “Godzilla” El Niño of the winter of 2015-16 that was supposed to bring so much rain? No?

That’s because despite having some of the strongest El Niño conditions on record (the madre of all Niños?), that winter wasn’t exactly a drought buster.

From December 2015 through March 2016, Phoenix picked up 1.52 inches of rain, according to National Weather Service statistics. The last measurable rain in that period fell on Jan. 31. Normal for that four-month span is 3.7 inches.

So what are the Niños?

They’re names given to weather conditions that are indicated by sea surface temperatures in the eastern Pacific Ocean.

El Niño, Spanish for little boy or Christ child, was so named because the phenomenon was first noticed in the 1600s by South American fisherman around the Christmas season. It is signified by the warmer than normal waters those fishermen noticed.

La Niña (Spanish for little girl) is the opposite of El Niño, which is probably why it was given that name. It occurs when waters in that part of the Pacific are cooler than normal.

Variances in ocean temperatures can affect weather in many parts of the world by influencing the position of the jet stream, upper-level winds that steer storm systems.

What can they mean for Arizona?

El Niño causes a great deal of excitement in the Southwest because it brings the promise of rain. The southern half of the country often sees wetter winters during El Niño years.

La Niña isn’t nearly as welcome around here because it usually offers a forecast of a warm, dry winter in the Southwest and cold, snowy times in the Northeast.

The 2015-16 El Niño was one of the strongest ever recorded with sea-surface temperatures peaking at about 2.3 degrees (Celsius) above normal. That may seem like a small amount, but as sea-surface temperatures go, it's a big deal.

While the warm water was there that winter, the jet stream didn't consistently stay in position to deliver many storms to the Phoenix area.

Other recent El Niño winters that were predicted to be very strong delivered mixed results.

The 1997-98 period from December through March saw 5.42 inches of rain, but the 1982-83 period saw just 3.51 inches (3.17 inches came in March).

La Niña winters are a bit more true to form.

The three most recent strong La Niña winters saw 1.83 inches of rain in 2010-11, 3.06 inches in 2007-08 and 2.99 inches in 1999-2000.

Last winter was considered a weak La Niña winter. After a strong start – 3.29 inches from December through February – it finished up with only .06 inch in March.

So why pay attention to the Niños?

All this isn’t to say that keeping track of ocean temperatures and the resultant El Niño or La Niña conditions isn’t important.

The monster El Niño of 2015-16 was a slight factor (not as much as long-term global warming) in record-setting temperatures globally in each of those years, according to NOAA. La Niña conditions can have a cooling effect on global averages.

Ocean temperatures can also affect the number and intensity of hurricanes, particularly in the north Atlantic.

But El Niño, La Niña or their ambivalent cousin we’ll just call El Neutral aren’t the deciding factor in what type of winter we’ll have. Any meteorologist will tell you they’re just one of several factors.

State Climatologist Nancy Selover said Pacific Ocean temps aren't the last word on our winter weather.

“I don’t think it’s that critical,” Selover said. “We are not typically, in Arizona, just pounded with rain if it’s El Niño and dry if La Niña. We’ve had some neutral years that have been really wet and some that are really dry. I’m not hanging my hat on any of that stuff. We’ll see.”